For one bottle* I’d add a small glass of inexpensive ruby port (like Vintage character), a couple of tablespoons of soft brown sugar, a cinnamon stick, a piece of star anise, a few cloves and a finely pared slice of orange peel, bring the whole lot slowly to the boil then immediately take the pan off the heat and infuse the spices for 20-30 minutes. Then remove the spices and reheat it carefully without boiling. Makes around 6 cups or glasses.
Other good bets for mulling are inexpensive unoaked Portuguese and Spanish reds (oak aged wines can taste bitter when they’re mulled). And as with with cooking with wine never mull a wine you wouldn’t be prepared to drink on it’s own!
What sort of wine do you like to mull? Do you have a favourite recipe?
* If you use more than one bottle increase the amount of port and sugar proportionately but you don’t need to double or treble the spices.